The overall program comprises the study of Trichomonas vaginalis, and Tritrichomonas foetus for comparison by cell fractionation, biochemical and electron microscopic methods in order to gain insight into the biochemistry and subcellular organization of trichomonds. T. vaginalis, the causative agent of human trichomoniasis, is wide spread in the USA and knowledge of it is not in proportion with its importance. Research proposed for the last year of the grant is concentrating on the following aspects, all following from results of past years. End products of the carbohydrate metabolism will be quantitated to obtain carbon and redox balances for different conditions of incubation. Through this more insight will be obtained into regulatory processes of trichomonad metabolism. The anaerobic processes in isolated hydrogenosomes will be studied to find the similarities and differences between the two species at the anaerobic level. In addition to exploring the hydrolase spectrum of T. vaginalis, its major protease will be purified in order to compare it with the protease purified from T. foetus and thus add to our understanding of species differences in hydrolases. Release of the protease and of other hydrolases by the cells will be studied.